Electrical indicator



(No Model.)

O. B. SHALLENBERGER.

ELECTRICAL INDICATOR.

No. 380,947. Patented A r. 10, 1888.

WWW/w.

N, PETERS, PhntwLlllmgmphur, Washington, D. c.

NITED STATES PATENT OrErcE.

OLIVER B. SHALLENBERGER, OF ROCHESTER, ASSIGNOE TO THE W'ESTING HOUSE ELECTRIC COMPANY, OF PITTSBURG, PENNSYLVANIA.

ELECTRICAL INDICATOR.

SPECIFICATIONforming part of Letters Patent No. 380,947, dated April 10, 1888.

Application filed December 9, 1887. Serial No. 257,408. (No model.)

To all whom it may concern:

Be it known that I, OLIVER B. SEALLEN- BERGER, a citizen of the United States, residing in Rochester,in the county of Beaver,in the State of Pennsylvania, have invented certain new and useful Improvements in Electrical Indicators, (Case No. 187,) of which the following is a specification.

The invention relates to the class of apparo ratus employed for indicating at any time the current upon an electric circuit; and the object is to provide convenient means for determining and regulating at a central station the potential upon the work-circuit.

r The invention consists in deriving from the main circuit currents having a potential directly dependent upon the difference of potential at the terminals of the generator and currents upon a second circuit having apotential 2o dependentupon or affected by the loss or drop upon the lines when that loss is sufficient to cause an appreciable effect on the work-circuit. The effects of the currents thus derived are balanced against or caused to oppose each other, and the resultant indicates the difference of potential existing upon the work-circuit.

The invention will be described particularly in connection with the accompanying drawings, in which Figurelis a diagram illustrating an organization of circuits for carrying out the invention, and Fig. 2 is a detail of the converter. Fig. 3 is a modification.

Referring to Fig. 1, A represents an electric generator or other suitable source of altenating electric currents, and L L represent two lines leading from the respective poles thereof to a Work-circuit, D D", containing translat o ing devices d d, designed to be operated by electrical currents.

A converter, 0, has its primary coil,p, connected between the conductors L and L, and its secondary coil, 8, connected by means of 1,5 conductors 5 and 6, through the coil or solen' oid b of an indicating device, F. These conductors preferably include an artificial resistance, r,which is adjustable, and an additional resistance for which an incandescent lamp, b,

maybe conveniently used, to localize the heating efiect of the current and render the readnot be inconveniently large.

ings practically independent of the tempera ture of the coil 1), the resistance of which is small compared to the resistance d.

The object of the converter Ois to cut down or reduce the difference of potential at the terminals of the coilsb to a convenient degree, so that the resistance in the circuit 5 6 need This coil b acts upon a core, e,which is preferably composed of soft-iron wires insulated from each other. The core is suspended upon one arm of a pivoted lever, E, carrying a pointer, F, applied to an indicating-plate,F. The other arm of this le ver carries a core,f, similar to the core 6, and this is acted upon by a solenoid,c. The solen oid e is connected in the secondary circuit of a converter, 0 This converter 0 is introduced for the purpose reducing the current flowing through the coils c in some determinate ratio to the current passing through the conductors Laud L so as to avoid sending inconveniently large currents through the convolu tions of the coil 0 and through the conductors 7 8,which lead to the coil 0.

The converter 0 has its primary coil in the direct circuit of the line L, and it consists in this instance merely of a section of the conductor L passing through it; or, if desired, it may be wrapped once or twice about the core 7:. This core is constructed in any convenient manner preferably, however, of thin plates of soft iron insulated from each other. The secondary coil, 8, consists, preferably, of any required number of turns of insulated Wire, different portions of which may be included in the circuit of the conductors 7 and 8 leadingto the coil 0, as required. For this purpose conductors 9 9 9 lead from different pointsin the length of the secondary coil, 8, to contact-points or binding-screws k 7:, with which the conductor 7 may be connected for the purpose of adjusting the instrument to different currents and different losses of potential upon theline.

It is designed that the effects of the two coils upon their respective cores shall be such as to maintain a balance when no current is flowing in the coil 0 and a normal difference of potential exists at the terminals of the generator. When very little current flows through the main-line circuit L L the difference of p0ten= tial at the generator is practically the same as at the lamps or translating devices d d,- but as the current increases the loss in the line increases proportionately, and hence to pre serve the normal difference of potential at the translating devices the difference of potential at the generator must be increased. This would tend to throw the indicator out of balance, carrying the pointer F toward the right hand,but for the action of the coil c,which,being traversed by a current proportionate to the main current, tends to restore the equilibrium. If the loss in the main-line circuit amounts to, say, approximately ten per cent. of the useful work at the full load, then the difference of potential at the dynamo should be ten per cent. higher than when the load is very small. If, therefore, the coil 0 has an effect equal to one-eleventh that of the coil 12, the balance will still be approximately maintained. When operating under half the full load, the loss is five per cent., and the effect of the coil 0 is approximately five per cent., since the current passing throughit is reduced to one-halfits former value. In this manner the indicator will serve to show when the difference of potential at the translating devices is at its required value.

Instead of having the currents induced in the two secondary coils act in opposition through two solenoids or magnets, shunt and series coils may act upon a single corein opposition to each other and the resultant induced current be employed for operating the indicator. In Fig. 3 such a modification is illustrated. In this instance the coil 0 constitutes a portion of the primary coil of the converter, and the coil Z) a second portion, while a coil, 3, constitutes a secondary coil of the converter. The coil bis connected between the conductors L and L and the coil 0 is connected in the circuit of the conductor L The two coils are wound in opposition to each other,and the current induced in the secondary coil, 8, will be due to the difference between the effects of the currents in the two coils b and c. The effects of the coils b and c are such that the resultant current in the coil b maintains a balance at the proper electromotive force for the current passing, a weight 6 being opposed to the core f.

I claim as my invention- 1. An electric indicator consisting of two coils opposing each other, one coil receiving currents dependent upon the potential at the terminals of the source of electricity and the second receiving currents dependent upon the current in the work-circuit, and an indicating device operated by the resultant effect of said currents.

2. An electric indicator consisting of a converter having its primary coil connected in series with one of the supply-conductors leading to the work-circuit, a coil of insulated wire connected in circuit with the secondary coil of the converter, an indicating device coil ofinsulated wire connected in the secondary circuit, a second coil opposed thereto, means for supplyingsaid second coil with currents proportional to the difference of potential at the terminals of the source, and means actuated by said opposed coils for indicating the potential on the work-circuit.

4. The combinatiomwith the source of elec tricity and a work-circuit supplied therefrom, of a converter having its primary coil connected with said source, a solenoid connected in the circuit of the secondary coil, the conductor constituting the solenoid being adjustable with reference to its active length, a second solenoid acting in opposition thereto, a second converter, the secondary coil of which includes said second solenoid in its circuit, and conductors connecting the primary coil ofsaid second converter with the respective terminals of the source of electricity.

5. An electric indicator consisting of the coils b and c, the lever E, acted upon thereby, an electric converter having its secondary coil connected through the coil 0, a second converter having its secondary coil connected through the coil b, and means for supplying currents to the primary coils of the respective converters.

6. An electric indicator consisting of a converter the primary coil of which is designed to be connected in an electric circuit, means for adjusting the length of the conductor .constituting the secondary coil, a solenoid included in the secondary circuit, the length of the conductor constituting the solenoid being adjustable, a second solenoid acting in opposition to the first-named solenoid, a converter including the second solenoid in its secondary circuit, and an indicator affected by currents traversing said solenoids.

7. An electric indicator consisting of a converter the primary coil of which is designed to be connected in an electric circuit, means for adjusting the active length of the conductor IIO constituting the secondary coil, a solenoid included in the secondary circuit,a second solenoid acting in opposition to the first-named solenoid, and an indicator affected by currents traversing said solenoids.

In testimony whereof I have hereunto subscribed my name this 11th day of November, A. D. 1887.

OLIVER B. SHALLENBERGER.

Vitnesses: I

REGINALD BELFIELD, W. D. UPTEGRAFF. 

